Historic district stormwater management

My boss has asked me to dig around online and try to find out what other cities do to manage the stormwater runoff from awnings and canopies. More specifically, he's trying to find out what to do from the standpoint of Historic Preservation.

The city is concerned about the sheets of water that flow from these awnings and onto the sidewalks. Does anyone know of a way to prevent or mitigate the flow of water? Any thoughts would be greatly appreciated!

Aside from issuing everyone an umbrella, I don't really know what can be done. I haven't seen any type of guttering for awnings. I imagine you could compel something for canopies (being more structural than fabric awnings), but the question is a tough one. I'll be interested if you find anything.

Thats exactly what I was thinking... I've never heard of anything that would do anything to stop runoff from awnings. Canopies could probably just be sloped slightly to the rear and guttered from there.

What is the typical width of the sidewalk? I think sloping them towards the building may cause some unintended consequences (water damage tobuilding depending on the exterior material) and may not be a good idea. There are a lot of factors that may come into it, like shape of the canopy, width of sidewalk, how close to the street the canopies are allowed to go, etc.

I've seen restaurants with outdoor seating that have a canopy over the sitting area. The canopy is designed so that it holds the water in certain spots that have some holes punched through them so that the water drains away from where people sit and walk.

It may be a situation where you can solve the problem by requiring the storm water to be managed in a way that it sheet drains into a specific spot and handling on a case by case basis (which can bring up some other undesired consequences)

Managing stormwater from buildings in an environment with a high percentage of impervious surfaces is indeed tough. It can be next to impossible to manage prior to leaving the structure.

I would recommend considering best management practices and controls that can be incorporated into the existing infrastructure and landscaping. It can be done but in all likelyhood will not be easy (considering the historical aspects and percentage of built environment vs. natural) or cheap.